CN107942295B - Sparse antenna of forward-looking array SAR system - Google Patents
Sparse antenna of forward-looking array SAR system Download PDFInfo
- Publication number
- CN107942295B CN107942295B CN201710994386.6A CN201710994386A CN107942295B CN 107942295 B CN107942295 B CN 107942295B CN 201710994386 A CN201710994386 A CN 201710994386A CN 107942295 B CN107942295 B CN 107942295B
- Authority
- CN
- China
- Prior art keywords
- array
- antenna
- transmitting
- receiving
- sparse
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
- G01S7/03—Details of HF subsystems specially adapted therefor, e.g. common to transmitter and receiver
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/88—Radar or analogous systems specially adapted for specific applications
- G01S13/89—Radar or analogous systems specially adapted for specific applications for mapping or imaging
- G01S13/90—Radar or analogous systems specially adapted for specific applications for mapping or imaging using synthetic aperture techniques, e.g. synthetic aperture radar [SAR] techniques
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/88—Radar or analogous systems specially adapted for specific applications
- G01S13/89—Radar or analogous systems specially adapted for specific applications for mapping or imaging
- G01S13/90—Radar or analogous systems specially adapted for specific applications for mapping or imaging using synthetic aperture techniques, e.g. synthetic aperture radar [SAR] techniques
- G01S13/904—SAR modes
- G01S13/9043—Forward-looking SAR
Landscapes
- Engineering & Computer Science (AREA)
- Remote Sensing (AREA)
- Radar, Positioning & Navigation (AREA)
- Physics & Mathematics (AREA)
- Computer Networks & Wireless Communication (AREA)
- General Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Variable-Direction Aerials And Aerial Arrays (AREA)
- Radar Systems Or Details Thereof (AREA)
Abstract
The invention discloses a sparse antenna of a forward-looking array SAR system, which is a method for realizing effective coverage of an observation strip by comprehensively considering array element sparse arrangement, system signal-to-noise ratio, two-dimensional imaging quality and the like, researching a basic configuration mode of adopting a short densely-distributed uniform transmitting array and a long sparse uniform receiving array and utilizing a zero point of a transmitting beam to inhibit a receiving grating lobe and beam scanning; it not only greatly reduced array element quantity, still had following advantage: firstly, the transmitting antenna adopts a longer array antenna to form a narrow beam, so that the transmitting gain is improved, and a large receiving array element interval also provides a space for properly improving the receiving array element gain, so that the signal-to-noise ratio of the received echo is finally improved; secondly, narrow beams are emitted, the scene width of each beam is reduced, and conditions are provided for adopting a simple and efficient course-crossing distance migration correction algorithm; thirdly, the receiving array elements are uniformly distributed, so that fast algorithms such as FFT (fast Fourier transform) and the like can be adopted during course-crossing imaging, and the algorithm efficiency is further improved.
Description
Technical Field
The invention belongs to the field of radar antenna design and signal acquisition, and relates to a sparse antenna of a forward-looking array SAR system.
Background
In the field of radar three-dimensional imaging, forward looking array SAR has gained attention in recent years from many scientific institutions and researchers. The array antenna with the real aperture is used for low-altitude close-range earth observation of high-frequency-band (Ka, Ku and the like) radars, has the advantage of acquiring three-dimensional images of observation scenes in front of and below the platform in near real time, and provides a brand-new all-day all-weather working mode for ground object matching guidance, autonomous navigation, landing and the like of the flight platform. The forward-looking array SAR adopts the matched filtering of broadband emission signals to realize the high resolution of the distance direction, adopts the beam forming of the cross-course array antenna to realize the cross-course high resolution, adopts the virtual aperture synthesis of a plurality of pulses along the course to realize the high resolution along the course, and realizes the three-dimensional imaging of the front and lower observation scenes. Currently, forward looking array SAR systems face the following problems in array antenna design: because the array length is long and the signal wavelength is short, the traditional densely-distributed array antenna usually needs hundreds of array elements, so that the antenna cost is high, the design complexity is high, and the effective implementation of a forward-looking array SAR system is limited. How to effectively reduce the number of array elements becomes an important problem in the forward-looking array SAR, and the method has strong research value.
At present, three methods for effectively reducing the number of array elements of a forward looking array SAR are available: the method comprises the first step of an array non-uniform sparse method, wherein a forward-looking three-dimensional SAR model of an optimized linear array based on a simulated annealing method is published in 'computer engineering and application' in 2012 by main documents of Lulan, Zhangling and the like; the method reduces the number of array elements to a certain extent and avoids imaging grating lobes, but the non-uniform arrangement is not beneficial to the rapid processing of cross-course imaging, and the sparsity of the array is very limited. Second, a Multiple Input Multiple Output (MIMO) technology, the main documents of which are matsushi, zhuying red, and the like, "airborne forward looking Radar imaging algorithm of multiple input multiple output array" published in 2015 in the electric wave science, "Wei β m", Gilles m, "Initial art ino Radar Experiments" published in 2010 in European Conference on Synthetic Aperture Radar "; the array antenna sparse schemes based on time-sharing coherent MIMO are respectively provided, the number of array elements is effectively reduced, but because the aperture of the transmitting array element and the aperture of the receiving array element are only slightly larger than half of the wavelength, the transmitting gain and the receiving gain are very limited, and the radar action distance is small or the echo signal-to-noise ratio is low. Thirdly, array sparse sampling and compressive sensing methods, mainly including 'research on linear array SAR three-dimensional imaging method based on compressive sensing' published in aerospace newspaper by Wecisun army and Zhang Jingling in 2011 and 'Design of array for air imaging and bound SAR based on compressed sensing' published in 2014 by Gao Lei, Zeng Yonghu and the like; the method not only effectively reduces the number of array elements, but also realizes the cross-course super-resolution to a certain extent, but because the ground scattering sources are assumed to be sparse, the sparsity of most radar complex images is not high in practice, and in addition, the computation amount is huge, so that the further application of the radar complex images is limited. It can be seen that the above methods have some problems which are difficult to overcome in practical application, and limit their effective application.
Disclosure of Invention
In view of the above problems in the prior art, an object of the present invention is to provide a sparse antenna of a forward-looking array SAR system, which comprehensively considers aspects such as array element sparsity, system signal-to-noise ratio, and two-dimensional imaging quality, and studies a method of using a basic configuration mode of a short densely-distributed uniform transmitting array and a long sparse uniform receiving array, and using a zero point of a transmitting beam to suppress a receiving grating lobe and beam scanning to realize effective coverage of an observation strip, thereby significantly reducing the number of array elements, improving the transmit-receive gain and the system signal-to-noise ratio, ensuring the imaging quality and efficiency, and providing a new solution for designing an antenna of a forward-looking SAR system.
In order to realize the task, the invention adopts the following technical scheme:
a sparse antenna of a forward-looking array SAR system comprises a transmitting antenna and a receiving antenna, and is characterized in that the number of array elements of the transmitting antenna is
The number N of the array elements of the receiving antennar＝Lr/dr，minAnd the weighting window function of the transmitting antenna adopts a periodic window function;
where γ is the broadening coefficient of the beam null of the transmitting antenna, LrBeing receiving antennasTotal length; dr，minIs the optimal solution of the following optimization equation:
s.t.λ/2≤dr≤λ/Δθt
m≥γ
wherein m is a positive integer, drFor spacing of elements of the receiving antenna, Delta thetatλ is the operating wavelength of the system for the minimum width of the transmit beam.
Optionally, the weighting window function of the transmitting antenna adopts a periodic Hamming window or a periodic Hanning window.
Compared with the prior art, the invention has the following characteristics:
1. compared with a densely distributed array, the number of array elements is greatly reduced (see a simulation experiment);
2. the transmitting antenna adopts a longer array antenna to form a narrow beam, so that the transmitting gain is improved, and a large receiving array element interval also provides a space for properly improving the receiving array element gain, so that the signal-to-noise ratio of system echo is finally improved;
3. narrow beams are emitted, so that the scene width of each beam is reduced, and conditions are provided for adopting a simple and efficient course-crossing distance migration correction algorithm;
4. compared with a non-uniform sparse distribution method, the sparse antenna can adopt fast algorithms such as FFT (fast Fourier transform) and the like during cross-course imaging.
Drawings
FIG. 1 is a schematic diagram of a forward looking array SAR system observing the earth;
FIG. 2 is a transmit antenna pattern;
FIG. 3 is a two-way directional diagram of a transmit receive antenna;
FIG. 4 is the result of imaging a point scatter source;
FIG. 5 is a cross-sectional view of a point scatter source image;
FIG. 6 is the imaging result of a nine point scatter source.
Detailed Description
In order to make the technical solution and advantages of the present invention more apparent, the present invention is further described below with reference to specific embodiments in a forward looking array SAR system and the accompanying drawings.
The invention is mainly applied to radar imaging of the real-aperture array antenna, and is mainly applied to a short-distance imaging platform of a high-frequency array radar at present.
Fig. 1 shows a schematic diagram of a forward-looking array SAR system observing the earth. The carrier flies at a constant speed horizontally along the direction of the observation strips at the H meters above the observation strips, and the speed is v. The radar emission beam points to the front lower part of the platform (effective coverage of an observation strip is realized by adopting beam scanning, and an observation example under the condition of two beams is given in figure 1). Assuming that the receiving antenna and the transmitting antenna are independent array antennas, the transmitting antenna adopts an electrically-swept short densely-distributed array antenna, the receiving antenna adopts a long array antenna which is sparsely and uniformly arranged, and the two antennas are arranged in parallel and perpendicular to the flight direction of the platform, as shown in fig. 1. Defining the flight direction of the aircraft as a course along the X-axis; the receiving and transmitting array direction is a cross-course direction and is expressed by a y-axis, and the centers of the two arrays are zero points of the y-axis; the height direction is the z-axis, and the horizontal ground is the zero point of the z-axis. The directional arrangement of the three coordinate axes conforms to the rule of a Cartesian rectangular coordinate system. The steps of designing the sparse antenna of the forward-looking array SAR system are as follows:
step one, adopting a new antenna transceiving mode
The basic cases of a transmit-receive antenna are: the transmitting antenna adopts an electrically-swept short densely-distributed array antenna, and the receiving antenna adopts a long array antenna which is uniformly and sparsely arranged. Compared with the traditional single densely-distributed array antenna, the length of the transmitting antenna is very short, and the number of array elements is much smaller; because the receiving antennas are arranged sparsely, the number of array elements is much smaller, and the total number of the array elements is greatly reduced. Meanwhile, in order to meet the requirement of coverage of the observation strip of the forward-looking array SAR, the transmitting antenna needs to scan the observation strip, so that the phase-shifting electric scanning mode is more suitable. Therefore, the system works in the following way: for a certain observation area, the observation area is divided into a plurality of sub-areas according to the beam width, the transmitting antenna scans each sub-area in sequence, the receiving antenna receives the echo of each sub-area in sequence in the process, and the receiving array elements in the array antenna receive the echo of each sub-area simultaneously.
Step two, determining basic parameters of the antenna according to the resolution requirement
After the system transceiving mode is determined, the basic parameters of the antenna are determined according to the imaging requirements of the forward-looking array SAR system. The basic parameters for imaging are: radar range R, range resolution Δ R, cross-heading resolution Δ a, etc. And the working wavelength lambda of the system, the total length L of the receiving antennarCan be represented by the following formula:
where β represents a resolution broadening factor.
Step three, determining incidence relation of transmitting and receiving antenna parameters from grating lobe suppression angle
Suppose that the array element spacing of the receiving antenna is dr(drλ) is greater than N, the number of elements of the receiving antenna is Nr＝Lr/dr. Because the array element interval is enlarged, the aperture of the receiving array element can be correspondingly and properly increased, and the receiving gain is improved. However, the sparse arrangement of the array will bring the receive grating lobes to degrade the imaging quality, wherein the azimuth sin θ of the receive grating lobes under the condition of phase shift and weighting is not consideredr0The following equation will be satisfied:
in view of radar imaging, the receiving grating lobe can obviously reduce the cross-course peak sidelobe ratio and the cross-course integral sidelobe ratio of the imaging system, and cross-course imaging can be realized only by effectively inhibiting the grating lobe. Experiments show that a feasible method is to enable the zero point position of the transmitting beam to be the same as the receiving grating lobe position, and the zero point of the transmitting beam is utilized to effectively reduce the grating lobe level of the total receiving and transmitting beam.
The transmitting antenna adopts a uniform dense array, and the array element spacing is assumeddtIs lambda/2, and the length of the transmitting antenna is LtThen the number of array elements is
If the transmit antennas are appropriately periodically weighted and the broadening coefficient of their beam nulls is assumed to be γ (which is closely related to the window function of the transmit array, in general γ being 1 or 2), the null position θ of the transmit beam is then determinedt0Can be expressed as
It should be noted that the window function here is a periodic window function, that is, the positions of the beam zeros are periodic. Implementations have shown that some of the beam nulls of the window function are not periodic and cannot be used here. At present, through tests, a rectangular window function, a periodic Hamming window and a periodic Hanning window are all available.
To obtain a more ideal integrated sidelobe ratio level, the receive grating lobe must fall into the null position of the transmit beam, i.e. the following conditions are satisfied:
thus, the receiving array element spacing drAnd the length L of the transmitting antennatSatisfy Lt＝mdrWherein m is not less than gamma, dr＞λ。
And step four, determining an expression and a constraint condition of the total array element number, and establishing an optimization equation.
The total number N of array elements of the transmitting antenna and the receiving antenna is determined according to the constraint relation in the formula (4)trCan be expressed as:
as can be seen, the expression (5) is a monotonically increasing function of the variable m, the smaller the value of which is the smaller the function value,and the minimum value is m ═ γ, the variable m in formula (5) can be replaced with γ. If assume λ, LrAnd y are known, then when m ═ y,
when the value of equation (5) is the minimum value
At this time, the length of the transmitting antenna
Transmit beam width
However, due to LtThe transmission beam width is very narrow when larger, even far smaller than the width theta of the observation stripcThe problems of large scanning number, difficult beam control, and less receiving array elements affecting sidelobe suppression in subsequent beam forming are caused. Thus, LtIt cannot be infinite, but there is a minimum scan beam width Δ θtSo that L istMust be less than a certain value, and drMust also be less than a certain value, i.e.
Thus, according to equations (5) and (6), the total number of array elements can be expressed as drThe equation for the linear constrained optimization for the independent variable is shown below.
Wherein the objective function is a convex function and the constraint is linear.
Step five, solving an optimization equation with constraint and determining parameters of the transmitting and receiving antenna
The above optimization equation is a linear approximationThe convex optimization equation of the beam can be solved by utilizing a Lagrange multiplier method to obtain the optimal solution d of the equationr，min. From this optimal solution, the following parameters of the system can be uniquely determined, including: transmitting antenna length Lt＝γdr，minNumber of transmitting array elements
Number of receiving array elements Nr＝Lr/dr，min. To this end, an unknown parameter γ and a window function of the transmit and receive antenna weights are not determined, and γ depends on the transmit antenna window function.
Step six, determining the window function of the transmitting and receiving antenna according to the radar imaging quality requirement
As can be seen from equation (4), the smaller γ is, the smaller the total number of transmit-receive array elements is, but the cross-heading integral sidelobe ratio may be higher, so the value of γ should be discussed according to the imaging quality. The array antennas of the forward-looking array SAR are arranged in a cross-course mode, and the cross-course high resolution is realized by adopting the beam forming of the cross-course array antennas, so that three indexes of cross-course resolution, cross-course peak sidelobe ratio and cross-course integral sidelobe ratio are considered. Experiments show that the transmitting-receiving split array antenna mainly has the following characteristics: (1) because the receiving grating lobe is effectively restrained, the cross-course resolution is only related to the weight of the receiving array and is not closely related to a transmitting directional diagram. (2) The cross-course peak sidelobe ratio, although also related to the transmit pattern, depends mainly on the sidelobe level of the receive array weighting process and also easily achieves a more satisfactory sidelobe level. (3) The cross-course integral sidelobe ratio is very close to the weighting processing of a transmitting directional diagram and a receiving array. Meanwhile, simulation experiment results show that the cross-course integral sidelobe ratio level is related to the following three points: (1) to achieve a more desirable level of integrated sidelobes, all receive grating lobes must be effectively suppressed by the nulls of the transmit beam. (2) If the rectangular window is adopted to weight the transmitting array, even if the receiving array adopts a deeper weighting function, the integral sidelobe ratio is larger than-10 dB, namely gamma cannot be 1; therefore, the weighting window function of the transmitting antenna can adopt both a periodic Hamming window and a periodic Hanning window, where γ is 2. (3) If the Hamming or Hanning window is adopted to weight the transmitting array, the integral sidelobe ratio is less than-10 dB as long as the weighting depth of the receiving array is less than-30 dB, and the requirement of cross-course imaging is met. Therefore, the minimum value of γ should be 2, and the transmit-receive antennas all adopt a periodic window function with a certain depth, so that the imaging requirements of the forward-looking array SAR system can be met. For example, in the following embodiments, the transmitting antenna employs a Hamming window function and the receiving antenna employs a Chebwin window function.
Specific examples are given below and the feasibility of the method of the invention and its imaging quality are verified.
Assuming that the wavelength of a transmitting signal is 3 mm, the length of a receiving antenna is 9.6 m, and if a uniformly densely distributed array is adopted and the distance between adjacent array elements is 1.5 mm, the number of the receiving array elements is 6400. If the method is adopted, the beam width can be infinitely small, the number of the transmitting array elements and the receiving array elements corresponding to the optimal solution is respectively 114, the total number of the array elements is 228, and the number of the array elements is reduced to 3.6 percent of the original number. At this point, the transmit beam width is about 0.035 radians. Assuming an azimuth beam width of 30 degrees (0.52 radians) and a degree of overlap of adjacent beams of 10%, the number of scanned beams is approximately 17. If the minimum beam width is assumed to be 0.07 radian, the number of transmitting array elements is reduced to 56, the number of receiving array elements is increased to 228, the total number of array elements is increased by 25%, and the number of scanning beams is reduced to 9. At this time, compared with the dense array mode, the array element is about 4.5%, and the number of the array elements is also remarkably reduced. The basic parameters of the simulation experiment are shown in table 1.
TABLE 1 basic parameters of simulation experiments
| Center wavelength (mm) | 3 | Total length of receiving antenna (m) | 9.6 |
| Pulse Width (MHz) | 500 | Scene center slope distance (km) | 1 |
| Pulse time width (mu s) | 2 | Cross course resolution (m) | 0.5 |
| Sampling frequency (MHz) | 600 | Distance resolution (m) | 0.55 |
(1): fig. 1 shows a dual-path pattern for transmission and reception with 56 transmit array elements and 228 receive array elements, where the transmit beams are weighted with a Hamming window, and the transmit beam width is 0.07 radians (about 3.7 degrees), as shown in fig. 2. And the receiving array carries out windowing processing during imaging, and the window function is a Chebyshev window of-35 dB. FIG. 3 shows a directional diagram of a transmitting-receiving double-pass, wherein the peak sidelobe ratio is-35 dB, and the integral sidelobe ratio is-17 dB, which completely meets the requirement of cross-course imaging.
(2): assuming a scene center slope of 1 km, the cross-heading resolution is about 0.5 m. Meanwhile, assuming that the transmitted pulse is a chirp signal, the signal bandwidth is 500MHz, the pulse width is 2 microseconds, and the range-direction window function is a chebyshev window of-30 dB, the range-direction resolution is about 0.5 meters. FIG. 4 shows a two-dimensional imaging of a point scattering source at the center of the scene, and FIG. 5 shows a distance-wise and cross-course profile of the scattering source image. The imaging method adopts a Chirp Scaling imaging algorithm.
(3): the echoes of 9 point scattering sources in a shape of a Chinese character 'tian' were simulated. Wherein, the amplitudes of the 9 point scattering sources are the same, the phases are random, and the distance between the adjacent point scattering sources is 1 meter. Fig. 6 shows the imaging results of these 9 point scattered source echoes.
It can be seen that with this antenna configuration, the present invention also achieves efficient imaging and accurate localization of all point scatter sources. The experimental results show that the method can effectively realize the cross-course imaging of the forward-looking array SAR, obviously reduce the number of array elements and is beneficial to the realization of the forward-looking array SAR antenna.
Claims (2)
1. A sparse antenna of a forward-looking array SAR system comprises a transmitting antenna and a receiving antenna, and is characterized in that the number of array elements of the transmitting antenna is
The number N of the array elements of the receiving antennar＝Lr/dr，minAnd the weighting window function of the transmitting antenna adopts a periodic window function;
where γ is the broadening coefficient of the beam null of the transmitting antenna, LrIs the total length of the receiving antenna; dtFor transmitting antenna element spacing, dr，minIs the optimal solution of the following optimization equation:
s.t.λ/2≤dr≤λ/Δθt
m≥γ
wherein m is a positive integer, drFor spacing of elements of the receiving antenna, Delta thetatλ is the operating wavelength of the system for the minimum width of the transmit beam.
2. The sparse antenna of claim 1, wherein the weighting window function of the transmitting antenna is a periodic Hamming window or a periodic Hanning window.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710994386.6A CN107942295B (en) | 2017-10-23 | 2017-10-23 | Sparse antenna of forward-looking array SAR system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710994386.6A CN107942295B (en) | 2017-10-23 | 2017-10-23 | Sparse antenna of forward-looking array SAR system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107942295A CN107942295A (en) | 2018-04-20 |
| CN107942295B true CN107942295B (en) | 2021-07-30 |
Family
ID=61935586
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710994386.6A Active CN107942295B (en) | 2017-10-23 | 2017-10-23 | Sparse antenna of forward-looking array SAR system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107942295B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108872980B (en) * | 2018-06-19 | 2022-06-03 | 电子科技大学 | Self-adaptive through-wall imaging method based on narrow-band system |
| CN109407091A (en) * | 2018-10-25 | 2019-03-01 | 清华大学 | Gothic mimo antenna array and safety check imaging device |
| CN112399554A (en) * | 2019-08-15 | 2021-02-23 | 华为技术有限公司 | Positioning method and device thereof |
| CN112632795A (en) * | 2020-12-30 | 2021-04-09 | 中国民用航空总局第二研究所 | Implementation method for reducing beam width of course beacon array antenna |
| CN112803174B (en) * | 2021-01-26 | 2022-03-15 | 上海交通大学 | Large-interval phased array based on zero scanning antenna and grating lobe suppression method |
| CN113268853B (en) * | 2021-04-14 | 2022-12-16 | 中国电子科技集团公司电子科学研究院 | Antenna directional pattern optimization method and device and readable storage medium |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102313888A (en) * | 2010-06-29 | 2012-01-11 | 电子科技大学 | Linear array SAR (synthetic aperture radar) three-dimensional imaging method based on compressed sensing |
| CN103682677A (en) * | 2013-11-14 | 2014-03-26 | 中国科学院电子学研究所 | Airship radar conformal thinned array antenna and its signal processing method |
| CN103762412A (en) * | 2013-12-31 | 2014-04-30 | 中国科学院电子学研究所 | Onboard downward-looking 3D SAR sparse array antenna laying method |
| CN103869316A (en) * | 2014-03-27 | 2014-06-18 | 西安电子科技大学 | Method for super-resolution imaging of foresight array SAR based on sparse representation |
| CN104793206A (en) * | 2015-04-28 | 2015-07-22 | 西北工业大学 | Imaging method through transmitting grating lobes |
| CN105137430A (en) * | 2015-07-30 | 2015-12-09 | 中国人民解放军西安通信学院 | Forward-looking array SAR echo sparse acquisition and three-dimensional imaging method |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8258996B2 (en) * | 2007-05-08 | 2012-09-04 | The Johns Hopkins University | Synthetic aperture radar hybrid-quadrature-polarity method and architecture for obtaining the stokes parameters of radar backscatter |
-
2017
- 2017-10-23 CN CN201710994386.6A patent/CN107942295B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102313888A (en) * | 2010-06-29 | 2012-01-11 | 电子科技大学 | Linear array SAR (synthetic aperture radar) three-dimensional imaging method based on compressed sensing |
| CN103682677A (en) * | 2013-11-14 | 2014-03-26 | 中国科学院电子学研究所 | Airship radar conformal thinned array antenna and its signal processing method |
| CN103762412A (en) * | 2013-12-31 | 2014-04-30 | 中国科学院电子学研究所 | Onboard downward-looking 3D SAR sparse array antenna laying method |
| CN103869316A (en) * | 2014-03-27 | 2014-06-18 | 西安电子科技大学 | Method for super-resolution imaging of foresight array SAR based on sparse representation |
| CN104793206A (en) * | 2015-04-28 | 2015-07-22 | 西北工业大学 | Imaging method through transmitting grating lobes |
| CN105137430A (en) * | 2015-07-30 | 2015-12-09 | 中国人民解放军西安通信学院 | Forward-looking array SAR echo sparse acquisition and three-dimensional imaging method |
Non-Patent Citations (1)
| Title |
|---|
| 综合孔径辐射计二维稀疏天线阵列排列方法;董健等;《微波学报》;20090430;第25卷(第2期);第83-86页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107942295A (en) | 2018-04-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107942295B (en) | Sparse antenna of forward-looking array SAR system | |
| CN101556328B (en) | Constructing method of airborne radar space-time two-dimensional filter based on clutter covariance matrix | |
| CN104977582B (en) | A kind of deconvolution method for realizing the imaging of scanning radar Azimuth super-resolution | |
| CN107976660B (en) | Missile-borne multi-channel radar ultra-low-altitude target analysis and multi-path echo modeling method | |
| CN105137430B (en) | The sparse acquisition of echo of forward sight array SAR a kind of and its three-D imaging method | |
| CN107976673B (en) | MIMO radar imaging method for improving imaging quality of large-scene target | |
| CN106772337B (en) | A kind of two layers of dielectric object localization method of frequency diversity array based on MUSIC algorithm | |
| CN103869316A (en) | Method for super-resolution imaging of foresight array SAR based on sparse representation | |
| CN111257878B (en) | Wave form design method based on pitching dimensional frequency intra-pulse scanning high-resolution wide-range SAR | |
| CN110412570B (en) | HRWS-SAR imaging method based on spatial pulse phase coding | |
| CN111537997B (en) | Three-dimensional radar imaging method based on MIMO and compressed sensing technology | |
| CN102901964A (en) | Two-dimensional multi-aperture scan synthetic aperture radar (SAR) imaging method | |
| CN110346794A (en) | A kind of distributed radar imaging method of most optimum distribution of resources | |
| CN114002673A (en) | Satellite-borne passive SAR non-cooperative signal sensing system and multi-dimensional parameter estimation method | |
| CN101059563B (en) | Synthetic aperture radar impulse phase shift method | |
| CN104749573A (en) | Sparse stepped-frequency SAR imaging method under spatial-frequency-domain two-dimensional condition | |
| CN106291547B (en) | Doppler ambiguity component Adaptive Suppression method based on antenna radiation pattern auxiliary | |
| CN113359131A (en) | SAR low-interception radio frequency stealth system and design method thereof | |
| CN112180368A (en) | Data processing method, device, system and storage medium | |
| Zhang et al. | Multi-beam Doppler beam sharpening approach for airborne forward-looking radar imaging | |
| CN115015925A (en) | Airborne array radar super-resolution forward-looking imaging method and device based on improved matching pursuit | |
| CN110376586B (en) | Distributed MIMO radar moving target detection method based on chromatography principle | |
| Zeng et al. | Super-resolution electromagnetic vortex SAR imaging based on compressed sensing | |
| CN106908793A (en) | Ka wave band along-trade INSAR systems and its method of work | |
| Zhang et al. | Wide-swath ip-sar |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |